Albus Severus Potter
Just before Albus Severus, Harry Potter's second son, boarded the Hogwarts Express, Harry handed him a letter.
"Read it today when you are alone and don't tell your brother about it. I want only you to read it, OK, Al?"
"OK, Dad," Albus replied, looking mystified by the letter and then keeping it in his pocket.
Albus waved and waved to his parents until they grew smaller and were out of his sight.
"Come on, Al, let's find a compartment," Rose said and together they walked along until they found an empty compartment. James was sitting in a separate compartment with his friends and Al didn't want to be teased about ending up in Slytherin again so, he was content to be sitting with Rose. He suspected Rose also felt a bit nervous about what house she'll end up in.
"I hope I'm not in Slytherin, I'll ask the Hat not to put me there," Albus thought to himself.
"Ravenclaw wouldn't be bad either, after Gryffindor, I mean," Rose spoke suddenly, as if she'd read his mind.
"Yeah Rose, but all of our parents were in Gryffindor and now James too, so I really want to be in Gryffindor as well," Albus replied.
"Right. You know I was going through our textbooks and I think my favourite subject is Transfiguration," Rose announced, changing the subject.
"Uh-huh," Albus said, absent-mindedly fingering his father's letter that was in his pocket.
"Rose, I'm just going to be back in a minute, I need to find the bathroom," Albus lied to his cousin, wanting to read his father's letter alone. Going out of the compartment, he walked along until the end of the train to a secluded spot.
Taking out the letter, Albus began to read. Harry had written the letter to Albus to explain the significance and reason of Albus Severus' name to him. He started out with Lily Evans' childhood and her friend Severus Snape. Then he mentioned his parents (Albus' grandparents), meeting at Hogwarts and getting married, having Harry and finally being killed by Voldemort in his failed attempt to kill Harry. Harry then outlined his years at Hogwarts and Severus Snape's secret efforts to help and save him all those years. Severus Snape had become a teacher at Hogwarts just to protect Lily's son. And he had died for that purpose too. In fact, it was his role as a secret spy for Dumbledore that helped Harry and the Order to battle and defeat the Death Eaters and save Harry's life at several occasions. And he did all of it due to his love for Lily.
When Albus finished reading the letter, his vision was blurred. A tear rolled onto his cheek as Albus cried for Severus Snape, for the grandparents he had never met, and the bravery of all the people fighting against Voldemort. After a while, Albus wiped the tears away and went back to his compartment. He knew now which house he wanted to be in.
When the Sorting Hat was put onto Albus Severus Potter's head, Albus asked to be put into Slytherin and he was. This was because he wanted to show that Slytherins could be as brave and loyal as the men he had been named after.